Zadania z chemii IB SL

Estimate the absorbance of a 0.400 $\mathrm{mol\,dm^{-3}}$ solution of nickel(II) sulfate.

Calculate the mass of solid potassium hydroxide that has to be weighed out.

Describe how the student should prepare this standard solution from the weighed solid using a 250.0 $\mathrm{cm^3}$ volumetric flask.

The student pipetted 25.00 $\mathrm{cm^3}$ of the potassium hydroxide solution into a conical flask and titrated it with nitric acid, $\ce{HNO3(aq)}$, of concentration 0.1250 $\mathrm{mol\,dm^{-3}}$. The burette readings before and after the titration are…

Explain why the potassium hydroxide solution has to be standardized before it is used in the titration. Assume that there are no systematic errors in the procedure.

4.06 g of hydrated magnesium chloride, $\ce{MgCl2*6H2O}$ ($M_\mathrm{r}$ = 203), is dissolved in water to make 0.250 $\mathrm{dm^3}$ of solution. What is the concentration of chloride ions, in $\mathrm{mol\,dm^{-3}}$, in this solution? A. 0.0400 B. 0.0800 C.…

A student compiles data on the solubility of bromine in water at different temperatures from several websites and textbooks. Source Temperature / °C Solubility of bromine A 5 3.90 g per 100 $\mathrm{cm^3}$ of water B 15 1.15 $\mathrm{cm^3}$ of liquid bromine…

A $20.00\ \mathrm{cm^3}$ sample of a solution containing 1.21 g of HA is titrated with $0.500\ \mathrm{mol\,dm^{-3}}$ sodium hydroxide solution, NaOH(aq). Exactly $27.40\ \mathrm{cm^3}$ of the NaOH(aq) is required to neutralize the acid completely. Determine…